1. Technical Field
The present invention relates to the structure of a hand tool for connecting and disconnecting a chain. More particularly, the invention relates to a chain tool that is both portable and easy to use.
2. Description of Related Art
FIG. 21 shows a conventional chain 9 with rapidly connectable and disconnectable end links. The two end links of the chain 9 are provided with two outer plates 91 on two opposite sides of the chain 9 respectively. Each outer plate 91 has a pin 92 and a through hole 93, wherein the through hole 93 has a large-diameter section 931 and a small-diameter section 932.
To connect the two end links of the chain 9 with the two outer plates 91, the pin 92 of each outer plate 91 is placed into the large-diameter section 931 of the through hole 93 of the other outer plate 91 through the corresponding hole in the corresponding end link. Then, the two end links are pulled in opposite directions so that the rollers 95 corresponding respectively to the pins 92 are moved away from each other to displace each pin 92 from the corresponding large-diameter section 931 to the corresponding small-diameter section 932 and to secure each pin 92 in position, thereby completing the connection of the two end links of the chain 9.
When it is desired to separate the two end links of the chain 9, referring to FIG. 22, the rollers 95 of the two end links that correspond respectively to the pins 92 of the outer plates 91 are simultaneously gripped with a pair of pliers 96 and are brought close to each other by applying a force to the pliers 96. Once displaced from the corresponding small-diameter section 932 to the corresponding large-diameter section 931, each pin 92 can be removed from the corresponding large-diameter section 931 to separate the two end links of the chain 9.
In bicycle riding, however, a rider would generally desire to carry as little load as possible during cycling; hence it is practically impossible for a cyclist to carry with them a large number of tools or a bulky tool like pliers. In view of this, the inventor of the present invention designed a “chain tool” as an improvement over its prior art counterparts. This chain tool is composed of two plate-shaped members that can be pivotally connected in a crossed configuration. Each plate-shaped member includes a first end and a second end opposite the first end, wherein the first end is provided with a hook portion to be inserted into a link of a chain. In addition, there is an opening between the first end and the second end of each plate-shaped member, and the opening of each plate-shaped member is configured to engage with the opening of the other plate-shaped member so that the two plate-shaped members can be pivoted with respect to each other about an axis defined by the engaged portion of the openings, in order to remove a quick link. While this chain tool is advantageously compact and portable, it leaves something to be desired in use. More specifically, the two plate-shaped members are engaged with each other via the openings only, without any securing structure between the openings; as a result, the two plate-shaped members tend to separate from each other in the assembled (i.e., engaged) state, which is disadvantageous to single-handed operation.